Suspension bearing

Abstract

A protruding portion is formed integrally on an outer ring in such a manner as to protrude from an outer raceway surface toward an inner raceway surface. A sliding portion is formed on an inner ring as a separate element from the inner raceway surface in such a manner as to protrude from the inner raceway surface toward the outer raceway surface. Due to the sliding portion being brought into contact with the protruding portion during a relative rotation of the inner ring and the outer ring, the sliding portion is formed by applying an elastic material such as rubber to the inner raceway surface by heating or bonding.

1. A suspension bearing comprising:
 a primary ring defining an annular primary raceway surface; 
 a secondary ring defining an annular secondary raceway surface, the secondary ring being coaxial with the primary ring; 
 a plurality of rolling elements supported between the primary and secondary raceway surfaces; 
 a primary engagement portion formed on the primary ring so as to protrude in a radial direction thereof toward the secondary raceway surface and extend in a circumferential direction of the primary raceway surface over a predetermined angle range; and 
 a secondary engagement portion formed on the secondary ring so as to protrude in the radial direction toward the primary raceway surface and extend in a circumferential direction of the secondary raceway surface over a predetermined angle range, the secondary engagement portion being formed integrally with the secondary raceway surface, 
 wherein the secondary engagement portion is brought into contact with the primary engagement portion to produce a frictional force for increasing a rotational torque within a specific relative rotation angle of the primary and secondary rings when the secondary ring rotates relative to the primary ring, and 
 wherein the secondary engagement portion is brought out of contact with the primary engagement portion within another specific relative rotation angle of the primary and secondary rings when the secondary ring rotates relative to the primary ring. 
 
     
     
       2. The suspension bearing according to  claim 1 , wherein the primary ring is fixed to an upper portion of a strut shaft and the second ring is fixed to a support portion on a vehicle body. 
     
     
       3. The suspension bearing according to  claim 1 , wherein the primary engagement portion comprises a plurality of primary engagement portions formed on the primary ring, and the secondary engagement portion comprises a plurality of the secondary engagement portions formed on the secondary ring corresponding to the plurality of primary engagement portions, and
 wherein the plurality of primary engagement portions are simultaneously brought into contact with the plurality of corresponding secondary engagement portions within the relative rotation angle range. 
 
     
     
       4. The suspension bearing according to  claim 1 , wherein one of the primary and secondary engagement portions is formed of a more elastic material than a material for the other. 
     
     
       5. The suspension bearing according to  claim 4 , wherein the primary engagement portion is formed of an elastic material separately from the primary raceway surface, and the secondary engagement portion is formed integrally with the secondary raceway surface. 
     
     
       6. The suspension bearing according to  claim 5 , wherein the primary ring comprises an inner ring and the secondary ring comprises an outer ring. 
     
     
       7. A suspension bearing comprising:
 a primary ring defining an annular primary raceway surface; 
 a secondary ring defining an annular secondary raceway surface, the secondary ring being coaxial with the primary ring; 
 a plurality of rolling elements supported between the primary and secondary raceway surfaces; 
 a primary engagement portion formed on the primary ring so as to protrude in a radial direction thereof toward the secondary raceway surface and extend in a circumferential direction of the primary raceway surface over a predetermined angle range; and 
 a secondary engagement portion formed on the secondary ring so as to protrude in the radial direction toward the primary raceway surface and extend in a circumferential direction of the secondary raceway surface over a predetermined angle range, 
 wherein the secondary engagement portion is brought into contact with the primary engagement portion to produce a frictional force for increasing a rotational torque within a specific relative rotation angle of the primary and secondary rings when the secondary ring rotates relative to the primary ring, 
 wherein the primary ring is fixed to an upper portion of a strut shaft and the second ring is fixed to a support portion on a vehicle body, 
 wherein the relative rotation angle range where the primary and secondary engagement portions are brought into contact with each other is determined based on a neutral position of a road wheel linked to the strut shaft, and 
 wherein the rotational torque is produced due to a contact between the primary and secondary engagement portions when a vehicle is driven to run straight ahead, and when the vehicle is steered to turn, the contact between the primary and secondary engagement portions is cancelled so as to cause the rotational torque to disappear or decline.